Concentration circuit for simplex printers



Oct. 171, 1932. G G |GHT CONCENTRATION CIRCUIT FOR SIMPLEX PRINTERSFiled June 19. 1931 Patented @et 11, 1932 liinirnn STATES PATENr orificei GEOGE (G. SLIGHT, OF KEW GARDENS, NEW' YORK, ASSIGNOR TO THE WESTERN'UNON TELEGRAPH COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW YORKCONCENTRATION CIRCUIT FOR SIMPLEX PRINTERS Application led June 19,1931. Serial No. 545,556.

centration or central station where a large 'inumber of lines areterminated before a small number of operators and is an improvement uponthe circuit arrangement disclosed in Patent 1,804,327 dated May 5, 1931.This improvement relates mainly to the manner in which thesignal batteryand line relay are removed from the line circuit upon answering a calland again inserting said relay and'signal battery in the line when themessage is concluded. In said patent this is accomplished l by means oftwo holding circuits which are interrupted periodically by a mechanicalinl terrupter.

The object of my invention is to simplify theV circuit arrangement,eliminate the Ine- Y chanical'interrupter and ei'ect' the re-insertionof the signal battery and line relay by means of a relay conrolled bythe breakdown lof a neonlamp in association with a slowacting chargingcircuit which is alternately charged and discharged.

My invention will be understood from the Vfollowing detailed descriptionin connection l with the accompanying drawing.

" corresponding parts in said patent.

The operators cord circuit and its associated equipment at the centralotiice and also that at the branch oi'iice are identical with te T eequipment at each branch station comprises a simplex printer SP, a keyswitch K, and Y, a. signal relay G. The branch station is connected by aline L to the central station.

fr With the key K in the position illustrated, the

i 'G and in the other position ot the key, the

relay G is disconnected, the line is grounded through the simplexprinter a'nd the energizing circuit of the printer operating motor M iscompleted.

At the central station, the line L is coni' nected through the windingot relay Cytofthe line plugs 1, 2, 3, 4," etc. rigidly located infrontof the respective operators. A circuit is normally closed over eachline from the central office to the branch oihces from the signalbattery or generator SB through ythe winding of line relayA overyconductor 5,

spring contact arm 6 and contact 7 ot relay B, conductor 8, line L,contacts 9 of key switch K, conductor 10 and Winding of rela G toground. W hen the operator at the ranch office sends a call by lirstshifting' the key K to connect the printer and then depressing any keyon the printer, thereby momentarily opening the line, the relayA Will bedeenergized and will remain in that condition because ot a short circuitwhich is completed around its Winding through the conductor l2 and itslett hand armature, conductor 13, back contact and right hand outerarmature of relay B and conductor 20. The right hand armature of linerelay A closes a circuit through the answer lamp l1. The lighting ofthis lamp indicates to any idle concentrator operator that this call maybek answered by attaching her printer cordv circuit to the correspondingline plug at her position.

The operators cord circuit comprises'the circuit arrangementinterconnecting the jack J with relays D, E and F and with the simpleXprinter SP2. rlhe tip contact in the jack J is connected to theright-hand tongue of relay E, and the back contact cooperating with thistongue is connected through winding 14 ot relay D to the plate elementof a two-electrode vacuum tube VT; the filament of the tube beinggrounded. One of the extra contacts on jack J is connected to ground,and the other cooperating extra contact is connected to the tongue ofrelay D. Winding 15 of relayD and the windings of relay E and F areconnected in series in a circuit extending from the Contact of relay Dto'ground, including a source ot' current 16. lThe lefthand tongue ofrelay E is connected to the tongue of relay l), and the back contactcooperating with this tongue is connected through abusy lamp 17, and asource ot current 18, to ground. The contact of relay F is included inthe motor operating circuit of simplex printer' SP2. The operatingcircuit for this printer extends from the front contact ot theright-hand tongue of relay E through the printer to the sourceotoperating current OB. l

The operation is as follows I With the lprinter at the branch otliceidle,

` the circuits are as shown in the drawing, With Y positive potentialnormally impressed upon the line L through the Winding 'of line relay Afrom .the signal generator SB. When the operator-.patine .branch oiceWishestortransmit to the central 'office she operates the key lll K', toconnect the printer and presses a key on the printer to momentarilyinterrupt the line,

"therebydeenergizing the line.relay A and lighting the "answer lamp l1Ias previously j described. When the central office operator connectsher jack J to-oii'e'of` the plugs',-the line L is connected through theAright-hand back contact of relay E, Winding lll of relay D, andvacuumtube to ground. i-At the fsame time the eXtra -contacts ofj'ack J areclosed/and complete a circuit from ground through the tongue and coil.l5 of relay D,

y{and}'thro'uggh the coils oft relays E fand F. The current Vflowingthrough the vacuum tube i froinfthev line AL is sulicient to VoperateirelayD butpis not sui'iicient to operate relay Operation of relay Econnects the printer .SBZ to the line-through its right-hand ,armailture and disconnects ,vacuumtube VT. y Operationof relay F: completesthe circuit to the operating motor of theprinter SP2. The in- `creasedcurrentdue to the series connection j laiiip v11.- It iszesseiiti of.generators OB and SB is suliicient `to operate relay C, Which in turnwill operate relay QB.. The operation voflock-.out relay B breaks :theconnection throughthe conductor. 1 8 at the contact y' 7 ,therebydisconnecting the'line lrelay A andfsi'gnal' generator; SB, fromthfefline. It

resistanceto ground, Relay A Will operi thafeiay 4vB haii remain vfinoperated 4position during. the entire time lthatthe branch otfice isconnected to the cen- V .H'tral oli'ice.. This is accomplished inthefol- -lovvingl'inanner-,Whenfthe relay B is'en- .ergized yby acircuit Vestablished through the right-hand armature and rontcoiitact ofrelay C, a holding circuit isestablished for VthefrelayB from generatorl9'through' the Winding vand inner left-hand armature ofV @relay B,conductor andback contact and armature of relay H to ground.

l'fl`l'ie'operation of relayl B also establishes vav .circuit fromgenerator-26 through the outer left-handarmature of relay B, conductor27,L -vlcighresistanceY 28 and thence through-the Vthree' parallelbranches of the interrupter circuit, thefirst consisting'of theneon lamp30 .andtheivvindingof relay lH, the second con,-l sis'ting of thecondenser 31a-nd theethird consisting of thek resistance 32j and theleft- Ihandl contact.- and armature j of -relay C.

These threeebranches are connected through the conductor 34 to theright-hand baclr coritact of relay C which is grounded through theright-hand armature When the relay C is deenergized.

When the relay C is energized during the transmission ofpiiiarkingsignalsfoyen the line, the circuit Vfrom 'generatorQG Ais opened atthe'right-liand back contact of relay C; but during spacing signalsrelay C is deenergized, thereby closing thercircuitl from generator 2.6Whichbegins tocharge the con denser 31. The relay C. is energized uponthe transmission of the next marking signal, thereby interrupting thecircuit of generator 26. vAny charge accumulated on thereondenser` 3lwill ybe immediately dissipated `through the circuit including theresistance BZand left-hand 'armatureotrelay y The values oli thejhi'ghresistancefQS and l capacity o' condenserjl` areVsode'signefdfthat a definite predetermined time requiredto charge thecondenser'to Vapot'ential suliic'ient `to break down the neonlamp'farfidpermit` a current to flow through the Windingofrelay H.During normal transmission o f's'ignals .over the line, the condenserWill-'be alternately charged and discharged but Withoutcausingtheoperationoi the neon lamp, the spacing signals being of suchshort`duration that the condenser is never charged to aV potential sufficientto break down the'gap in cthe lamp- Y t f` yAt thetermination oi thetransmission over, Ythe line, the operator atthe "central oliice removesher printer cord vcifrcuitso" that .Current f @eases tofA 'flew throughvf rlayg.

When. a suicient interval has elapsed for the condenser 3l 'tobe charged4to'theportentialof the generator 26,or tothe predeter- `,mined value,the vgases in the vneonflarnp 30.

lvvillbreali ,downl a'ldlperniita current y to ovvnthroughztheWindingpoflrelayl-I. As

the armature of relay H inoves'lfrmzits'back contact,4 the .holdingcircuit throughfconducvv;tor 25 isbrolremtherebyd'eenergining rel'ay.B.'` Asthe armatures lofthe 'rlayB moveto their back "contact's, acrtii'it is established ythrough conductor Sito-,Aconnect the line relayA and' signal' generator to the Aline. Thefinterrupter circuitAfroinfthe` .generator 26 is also'opened attheoutenlet't lhand armatureand contact ofrelay The line is thus restored tofiyts normal conditionand the concentration unit circuit at thefc'entral station isinire'adiness to receive an Lfincoming call. i v 7.,.

Forfthe purpose oillustrat'ion'have only shovvnone branch yolticev andthe corresponding equipment for onefline at thefcei'itral oicebut itWill be understo od.thatinffpr'ac-` .tice there areA numerous branchoinces With lines entering the .central oiice, Veach,1through ayc''incentration unit, circuit leacli "of vt/'liich is multipled to theplugsfatthe various'tur rets or operators positions.

, bodying a source of potential, a potential Vstoring device, and apotential-controlled gal)- Y 2. In an intercommunicating system of thecharacter described wherein a plurality of Van Vopening said holdingcircuit branch stations are connected to a central station,a receivingequipment atthe central station for each line, comprising a linesignaling relay and a source of signaling current, a lock-out relayunder control of a holding circuit for disconnecting said relay and4signaling current source when the line is being operated, and meanscontrolled directly by the line operating current for opening saidholding circuit.

3. In an intercommunicating system of the character described wherein aplurality of lbranch stations are connected to a central station, areceiving equipment at the central station for each line, comprising asignaling device normally connected to the line, means actuated by theseizure of the line by the central station operator to disconnect saidsignaling device from the line, a potential controlled device operatingto restore said device to the line, and means controlled by l. theintelligence signals for preventing the operation of said potentialcontrolled device.

4f. In an intercommunicating system of the character described wherein aplurality of branch stations are connected to a central station, areceiving equipment at the central station for each line, comprising aline signaling relay and a source of signaling current, a lock-out relayunder control of a holding circuit for disconnecting said relay andsignaling current source when the line is being operated, andinterrupter mechanism for embodying a circuit provided with a potentialstoring device and av potential controlled gap.

5. In an intercommunicating system of the character described wherein aplurality of branch stations are connected to a central station, areceiving equipment at the central station for each line, comprising aline signaling relay and a source of signaling current, 'a lock-outrelay under control of a holding circuit for disconnecting said relayand signaling current source when the line is being operated, meanscontrolled by the intelligence signals for opening said holding circuit,said opening means embodying a relay and series-connected gaseous gap,and a; o'- tential accumulator 1n shunt to said re ay and gap operatingto break down the gap and form a path for current through the relay.

6. In combination, aV printer line terminating at a central station, asignaling relay normally in said line, a second relay provided with aholding circuit and operating to disconnect said signalin relay from theline, means actuated upon t e seizure of the line to cause the operationof said second relay, and an electromagnetic interrupter for saidholding circuit, said means also causing the operation of saidinterrupter when the line is released.

In testimony whereof, I atix my signature.

GEORGE G. LIGHT.

